Consensus – Two Examples

For people with stock market experience, "consensus" is not something that usually is a strong buy signal. Here are some interesting examples – two from Enron showing how fragile a "consensus" can be, one from a geologist surveyed in one of the surveys supposedly showing a consensus among scientists.

These two quotes are from Kurt Eichenwald’s Conspiracy of Fools, which is a terrific read. (A certain House Committee played a role in this investigation.)

The next morning just after ten, Skilling stood beside Lay as a photographer snapped their pictures for an article in Fortune. They were more than happy to participate; already that year, in its annual rankings, Fortune had hailed Enron as America’s best-managed company, knocking General Electric from the number-one perch. (p.227)

After months of effort, Karen Denne from Enron’s public relations office landed the big fish: CFO magazine had selected Fastow as one of the year’s best chief financial officers. (p. 260)”Lay opened his briefcase and pulled out the latest issue of CFO magazine, glacing at the cover. The Finest in Finance. Lay smiled to himself. He found the table of contents, looking for Fastow’s name. Beneath it were the words: How Enron financed its amazing transformation from pipelines to piping hot. Lay turned to the article, “When Andrew S Fastow, the 37-year old CFO of Enron Corp. boasts that “our story is one of a kind’ he’s not kidding" it began”. Fastow was obviously as creative and sharp as Lay and Enron’s board of directors had come to believe” (p. 267)

I’m a geologist and have worked in and out of paleontology for the last 20 odd years. So I’m a ‘scientist’.

Is global warming real or not? Darn if i know but I do know that most of the so-called science is indeed ‘junk science’.

A few years ago a survey was circulated in our department. There were questions on climate change…emissions, etc. There were 8 of us surveyed and all in paleontology. Sounds nice BUT ‘our opinions’? None of us work in climatology…all have to listen to the weather forecast to know if it’s going to rain…’our opinions’? why would our opinion carry weight one way or the other?

I can tell you all about the intricate relationship of certain past lifeforms but I wouldn’t know which end of a climate chart on global warming is ‘up’. But sure enough, I keep reading these statiastics about ‘x’ number of scientists agree that global warming is due to …and blah, blah, blah. How the heck do these scientists know anything? I sure don’t and my colleagues don’t.

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I want to pause here and talk about this notion of consensus, and the rise of what has been called consensus science. I regard consensus science as an extremely pernicious development that ought to be stopped cold in its tracks. Historically, the claim of consensus has been the first refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled. Whenever you hear the consensus of scientists agrees on something or other, reach for your wallet, because you’re being had.

Let’s be clear: the work of science has nothing whatever to do with consensus. Consensus is the business of politics. Science, on the contrary, requires only one investigator who happens to be right, which means that he or she has results that are verifiable by reference to the real world. In science consensus is irrelevant. What is relevant is reproducible results. The greatest scientists in history are great precisely because they broke with the consensus.

There is no such thing as consensus science. If it’s consensus, it isn’t science. If it’s science, it isn’t consensus. Period.

In addition, let me remind you that the track record of the consensus is nothing to be proud of. Let’s review a few cases.

In past centuries, the greatest killer of women was fever following childbirth . One woman in six died of this fever. In 1795, Alexander Gordon of Aberdeen suggested that the fevers were infectious processes, and he was able to cure them. The consensus said no. In 1843, Oliver Wendell Holmes claimed puerperal fever was contagious, and presented compellng evidence. The consensus said no. In 1849, Semmelweiss demonstrated that sanitary techniques virtually eliminated puerperal fever in hospitals under his management. The consensus said he was a Jew, ignored him, and dismissed him from his post. There was in fact no agreement on puerperal fever until the start of the twentieth century. Thus the consensus took one hundred and twenty five years to arrive at the right conclusion despite the efforts of the prominent “skeptics” around the world, skeptics who were demeaned and ignored. And despite the constant ongoing deaths of women.

There is no shortage of other examples. In the 1920s in America, tens of thousands of people, mostly poor, were dying of a disease called pellagra. The consensus of scientists said it was infectious, and what was necessary was to find the “pellagra germ.” The US government asked a brilliant young investigator, Dr. Joseph Goldberger, to find the cause. Goldberger concluded that diet was the crucial factor. The consensus remained wedded to the germ theory. Goldberger demonstrated that he could induce the disease through diet. He demonstrated that the disease was not infectious by injecting the blood of a pellagra patient into himself, and his assistant. They and other volunteers swabbed their noses with swabs from pellagra patients, and swallowed capsules containing scabs from pellagra rashes in what were called “Goldberger’s filth parties.” Nobody contracted pellagra. The consensus continued to disagree with him. There was, in addition, a social factor-southern States disliked the idea of poor diet as the cause, because it meant that social reform was required. They continued to deny it until the 1920s. Result-despite a twentieth century epidemic, the consensus took years to see the light.

Probably every schoolchild notices that South America and Africa seem to fit together rather snugly, and Alfred Wegener proposed, in 1912, that the continents had in fact drifted apart. The consensus sneered at continental drift for fifty years. The theory was most vigorously denied by the great names of geology-until 1961, when it began to seem as if the sea floors were spreading. The result: it took the consensus fifty years to acknowledge what any schoolchild sees.

Finally, I would remind you to notice where the claim of consensus is invoked. Consensus is invoked only in situations where the science is not solid enough. Nobody says the consensus of scientists agrees that E=mc2. Nobody says the consensus is that the sun is 93 million miles away. It would never occur to anyone to speak that way.

I was reluctant to comment here but our geologist’s view of the matter is interesting. While admitting no specialist expertise in climate, he relegates most of climate as “junk science”. I don’t think that squares up with the rest of the anecdote. If one is not expert in climate science, one could hardly then dismiss it as junk. (Well aimed Exocet for the wrong reasons).

However, palaentologists are what we call, with warm affection, “soft-rockers” and I suspect our geologist is unfamiliar with the JORC codes and other Corporate mandatory reporting requirements.

Having said that, his point about “consensus” is interesting. If one is ignorant of a branch of science, then one can neither be pro or contra that branch of science.

As John’s extract from Crichton elabaorates, scientific consensus is not science, sensu strictu but politics.

Alas, Crichton’s fallacious thinking on the nature and role of consensus in science rears its ugly head once again.

As I’ve written before (http://www.abqjournal.com/opinion/guest_columns/275551opinion12-19-04.htm), Crichton either willfully or ignorantly misunderstands how science is done. Any interesting science – and by that I mean a science where active research is underway on unsettled questions – has a mainstream view and outliers. The mainstream view could reasonably be called “the consensus view” and is codified in textbooks and freshman overview courses and much of the day-to-day work of practicing scientists. The outliers poke away at the inconsistencies. This happens in astrophysics with the study of black holes, just as it does in climate change. There’s nothing unusual about the notion of “consensus science.” It’s done all the time. What else is a textbook if not the accumulation of a consensus – the body of knowledge on which the majority of the practitioners in a field agree? Over time, most of the outliers whose views lie outside that consensus turn out to be wrong, and the consensus holds. Occasionally, one turns out to be right, and the consensus is modified or overturned. By citing a list of people who bucked the consensus and turned out to be right, Crichton seems to suggest that we should ignore the consensuses, and believe all the outliers. This is obviously silly. We could come up with a far longer list of people who bucked the consensus and turned out to be wrong, and Crichton offers us no way to tell the difference.

The question is what to do in these situations where most of the scientists working in a field believe “A,” while some handful say no, it’s “B.” If it’s black holes, we can all watch with patient amusement while they duke it out. If the question has some public policy significance where action may be required before that argument can be sorted out, we have a longstanding tradition of getting a bunch of smart people together in an expert panel and asking their advice. This is how, for example, we try to figure out which flu strains to vaccinate against. The consensus view is that getting the MMR vaccine confers a statistically measurable reduced risk of disease to my child. The outlier view is that the vaccine confers some unmeasurable risk of autism. I know which choice I made.

This argument plays out in interesting ways in the political sphere, with both left and right hewing to the consensus view when it suits them and citing the outliers when that meets their needs. On the risks of low-dose radiation, for example, the right cites the consensus while the left makes the Crichton argument. On the risks of eating genetically modified foods, it again is the right citing consensus while the left clings to outliers. On the teaching of evolution, the Christian right is suddenly Crichton’s friend. “Teach the controversy!” On climate change, it’s the left hitching its wagon to the consensus while the right embraces the Crichton argument.

To be clear, I believe what Steve’s doing here is important outlier work. Outliers need to poke away. I don’t know if he’s right or not in his criticism of the consensus. Only time will tell, and I think it’s important that he keep at it. But I think throwing out the consensus every time one sees an alluring outlier is not a terribly helpful way to understand the state of any science.

John (Fleck), I think that there’s a qualified compliment here and if so I appreciate it. I agree that merely being an outlier or bucking an establishment is no guarantee of success. I also agree with your risk assessment – conventional views are very often reliable and attempting to be an outlier is a risky strategy.

I stumbled into what I’m doing now when Mann said that he had forgotten where MBH98 data was and Rutherford said that it didn’t exist in any one place. At that point, I thought that it would be interesting to try to replicate what they did, rather like doing a big crossword puzzle, not expecting any public interest in what I was doing. (At that point, I had never written an academic paper and was a businessman minding my own business.) I innocently assumed that audit-type or engineering-type replications would be standard in science before being applied to policy, little realizing that attempting to apply such a standard would itself end up becoming a story in itself.

I’m very conscious in business situations that “consensus” is fragile. When there is a consensus that it’s the time to buy stocks, smart money is usually heading for the exits. I realize that the analogy doesn’t apply to most science. A “consensus” in favor of quantum mechanics wouldn’t lead smart money to another explanation.

But in the climate field, and for multiproxy work in particular, I am really struck by the extaordinary prevalence of defects in the work of the most influential authors. While I’ve opined about MBH, IMHO the work of Jones, Briffa, Crowley etc. has equally glaring defects, which I’m in the process of documenting. I really don’t see how the corpus of present multiproxy work can be used to develop a valid scientific “consensus”. It seems odd that competent people should have adopted and applied such weak papers or that the replication effort should be so nonexistent, suggesting that there is a very strong ideological component or bias to the widespread acceptance and use of this weak material.

One clue may be in the IPCC process itself. One of the curious features of this process is the vast number of meetings at various relatively nice places all over the world, at which the scientists attempt to reach “consensus”. Yet for all the money and time spent on this, they make no attempt to do any engineering-quality due diligence. Most civilians assume that IPCC carries out engineering-quality due diligence rather than this type of negotiation.

In general, I prefer dealing with the particular rather than the general. In this case, the IPCC process, with its emphasis on a political form of process rather than an engineering audit, seems to result in a type of mutual reinforcement and excitement more characteristic of market phenomena and fads, than what I take to be the more usual scientific process where there is no attempt to negotiate and institutionalize a “consensus”. Thus the IPCC itself may be distorting the lens.

Sure. So no one’s gonna dispute e=mc2. But that’s not the sort of situation Crichton’s talking about. He himself says it this way: “Consensus is invoked only in situations where the science is not solid enough.” Agreed. But what do we do in situations where it’s not yet clear what the “true to itself” science is? We don’t have an e=mc2 sort of universal agreement on climate change, or the nature of black holes, or the safety/dangers of low-level radiation or genetically modified foods. So what are we supposed to do? My bet is that in medical school they taught Crichton what they teach today, which is the assembly of the best available advice of experts in the field – the consensus, if you will – on the best dietary advice to prevent heart disease, or the best treatments when you’ve got it, and so on. We do this routinely, and I’d be surprised if Crichton grabs his metaphorical wallet every time. It’s only when the “consensus,” or the majority expert opinion, or whatever you want to call it, comes to a conclusion that he doesn’t like that he heads of to Caltech to make a speech.

If not by seeking out majority expert opinion, how else might you suggest we approach decision-making in the face of scientific uncertainty?

FYI, my comment #6 was a reply to Sean Morris, not to Steve’s comment, which had not yet been posted when I clicked “Say it.”

I think Steve’s onto something far more useful here than Crichton – a specific critique of the process used in this case to come to our understanding of the majority of expert opinion, rather than the more general (and I would argue useless) critique that Crichton has offered, in which any appeal to consensus is automatically invalid ’cause that’s not how science works.

And yeah, Steve, it was a compliment, no qualification needed. You haven’t convinced me, and I still think the balance of the evidence weighs against you, but I still come back here regularly to read your stuff, because I think you’re raising important questions that need to be sorted out. I think believers in the consensus view (and I count myself among them) who reflexively ignore the arguments you’re raising do so at their own peril.

Another problem with the climate change issue is that the scientists involved in the IPCC process have not provided probabilities for any of the forecasts of potential future effects of increasing CO2. This may make it easy to write “consensus statements”, but those statements are worthless for rational policy evaluation since we need to be able to weigh likely costs and benefits to make policy decisions. It would be interesting to know what the “textbook” probability distribution for the GCM model forecasts would be. To any scientists who have been involved in the IPCC discussions, why has the issue of the probability of different outcomes been avoided? I am sure every scientist involved has his or her own subjective probability distribution over the potential outcomes. Has there been any attempt to amalgamate those into some “consensus view”?

First off, Crichton’s statement: “Consensus is invoked only in situations where the science is not solid enough.” — this is ridiculous. Is there not consensus on E=mc2? Is that weak science? It certainly under girds a significant body of work and some powerful evidence. On the contrary, consensus is what happens when the science IS solid enough. Crichton is quaint, and talks too much.

Consensus is a condition that is both a necessity to the foundation of any field of science shared by more than one scientist and a contingency that should be revisable when evidence suggests as such. Consensus is different from conformity, or ‘I’ll have what she’s having’. Consensus between scientists is built from evidence.

And the important thing is to keep asking questions of the evidence. That’s what scientists do, get paid for, use to vex and enlighten. Rigorous questioning is how a solid foundation is formed, a foundation from which the next steps can be taken. Cheers, Dr. McIntyre.

The fact (reiterating Mr. Fleck) is that Einstein had the scaffolding built of years of others’ solid work to launch from. Climatology, on the other hand, is a new field; the foundations are still under construction. I mean, how long did it take before the schools of oceanography and climatology were finally merged? Exactly.

What much of the evidence in this thread seems to be suggesting is that people don’t like it when politics and science become conflated. This is a legitimate concern.

Unquestioning conformity (or mindless consensus if you must) is the goal of power. And power only wants more power. To see scientists fall to a power play is sad (though far from unheard of). If people stop asking questions and challenging assumptions, power gathers and if we’re not careful we all could end up in some regrettable place (like Iraq) wondering which questions we forgot to ask before we agreed to consent to someone else’s explanations of the evidence.

It was a consensus of "experts" that said that Iraq had weapons of mass destruction, chemical, biological and possibly nuclear. All wrong.

Please tell us all what a consensus of anything means in the absence of cold, hard, evidence that has been checked and audited and replicated. I’ll tell you: NOTHING.

I have no idea whether you are being wilfully obtuse about Crichton’s speech, but let me tell you that from where I’m standing, the whole issue of anthropogenic climate change rests on nothing more than a confluence of opinions and religious beliefs amongst some scientists and quite a few bureaucrats.

That’s what Crichton is talking about: a consensus of "experts" proclaiming something to be true or "very likely" has happened many times in the history of science. These "expert consensuses" are not passive but have actively suppressed, delayed, censored or ignored contrary evidence which has later shown itself to be correct. The promotion of a scientific consensus in the absence of hard facts which are not in dispute or repeatable experiments deisgned to falsify propositions are not science at all, but political constructs whose purpose is suppression of knowledge and censorship of contrary evidence.

Climate scientists have played political games using scientific instruments such as climate models and multiproxy studies, with "peer-review" and "published in quality journals" as the main chess pieces, and look what they have reaped.

Now REAL politicians are involved in decisions of science because real money, real economies and real people’s lives are at stake. Some climate scientists have abused and continue to abuse science with political stunts and fake appeals to consensus and authority.

You don’t like political interference in science? That’s a shame because once you’ve started down the road of playing politics you’ll find that real politicians wielding real political powers will beat you every time.

This debate has become a semantic one (consensus vs. fact, etc). But the issues remain: science is subject to the forces of society, including the political apparatus that operates with and without the findings of science (or evidence, or reason, for that matter).

However, to accept a view without question, be that Crichton’s or theories of an impending ice age, is to ignore the practice of scientific inquiry (a hard won discipline, at that).

I think it is important to note that Crichton’s opinions are a reiterating (just as I am) Thomas Kuhn’s brilliant work from almost half a century ago. Kuhn’s conclusions were much the same: Consensus occurs when the theorem, axiom or findings have useful or powerful applications. Dissent occurs when the solution fails. The deeper implication here is that testing, debate and conflict are essential if any field of science is to get anywhere.

The role of scientists is to locate uncertainties and identify and work through problems. This is the only road to progress in a field. If the evidence is with you, go it alone. (If you want a new plasma screen TV, maybe you should rethink your findings.)
I suspect that the “science” that “proved” WMD as a “fact” was not in consensus. I think there was disagreement. Was the WMD information subject to verification outside Langley or MI5 et al? How was agreement developed? I suspect agreement was derived by rule of authority. People were brought into conformity (quibbling all the way) to match the interests of an underlying agenda.

John A: There’s a bit of confusion, I think, in your answer. There are two separate lines of arguments threaded together, I fear: the question about whether the notion of consensus is in itself inherently unscientific (which is the argument Crichton makes, and which is I think patently bogus) and the question of whether the alleged consensus in the case of climate change has been appropriately developed. I’m not sure how adding another example of a case in which a consensus was wrong helps here. In fact, I think your Iraq example is a bad one, but even if it’s apt, one can also cite tons of cases where the consensus turns out to be right, so we’re still stuck at square one in terms of having a way to tell the difference. I would ask you, John: when you face a medical decision, do you attempt to see what the bulk of experts in the field say should be done and then follow that course of action? Or do you follow the Crichton/Iraq example, and assume they must be wrong and do the opposite? I happen to believe asking the smartest people we can find for their consensus view remains a good choice, which is why we do it all the time. I think you’re right that a consensus isn’t worth much “in the absence of cold, hard, evidence that has been checked and audited and replicated,” and that’s what’s happening now. Good. You and I obviously have a different level of comfort in the replication that’s gone on, which is fine. I’ve seen a great deal of replication in various paleoclimate records that largely supports the notion that what’s happening today is anomolous relative to the last couple of millenia. Y’all obviously disagree. I think it’s a healthy debate as long as those of us on both sides of it are attentive to the work being done by people who come to conclusions we don’t like. (Again, that’s why I spend time reading Steve’s work.)

John English: I have to disagree with your assertion that “Crichton’s opinions are reiterating … Thomas Kuhn.” I think quite the opposite. Crichton says “the work of science has nothing whatever to do with consensus.” Fundamental to Kuhn’s analysis is the notion of “normal science,” which is the very definition of consensus – the agreed-upon body of knowledge and experimental program as understood by the majority of practitioners in a field. Under most conditions, Kuhn argues, that’s precisely how science works, and works quite well. To the extent that Crichton’s argument bears some resemblance to Kuhn’s it’s at the point where paradigms are overthrown because of an accumulation of anomalies that don’t fit the paradigm. But Crichton doesn’t say that. He specifically says *any* invocation of consensus is unscientific. That’s what’s so bizarre about Crichton’s attempt at explaining how science works, and what’s so frustrating when I see people repeatedly quoting him approvingly whenever mainstream science arrives at a consensus they don’t like.

It gets somewhat far afield from the subject here, but what’s usually missing from discussions of WMDs and Iraq is that what was being produced were threat assessments, not proofs. It was known that Iraq had had and used chemical weapons, and that they’d shown interest in biological and nuclear weapons. And it was known that Iraq had not done due diligance in showing that it no longer had such weapons or an interest in them. Therefore, all foreign groups who’d looked into the situation came to the conclusion that there still such weapons and a grave threat that left alone Saddam would try to get more.

Actually this isn’t all that far from AGHW, though. Of course it’s the warming crowd who both rely on threat assessments (climate models) AND prevent the inspectors (Steve et. al.) from verifying their data, but the conclusion I reach is still that the Hockey Team has things they’re trying to hide. Perhaps they don’t, but if so they have sure taken a funny way to reassure the public that they don’t have WM.. I mean flawed data.

Bruno Latour (Politics of Science) does a good job of explaining that we only have access to “fact” when we’re in a lab. Nobody has seen e=mc^2 written as divine revelation, the stars did not move in the sky for some scientist, and read “e=mc^2.” Rather, scientists have performed a bunch of expirements that conform with our understanding: e=mc^2. Experiments are facts.

Our understanding of electronics, computers, physics, robots, whatever: It is in our head, and it is stuff we know. And it’s always within our heads. To be sure, the universe has facts of its own, but we can never ever see them. We can perform experiments, and we can talk with people. But we can never magically know, by divine revelation, the facts of the universe. Experiment is our only gateway to fact.

When there is a set of explanations that we hold in our heads that we build machines out of and deeply trust, explanations such as “e=mc^s,” we can call that a black box. What is it? It’s a consensus of explanations. We no longer need to question it, test it, prod it- we just say “this is the thing, here’s how it works, end of story.” It’s a black box, and it just magically works, to our perception. It takes the form of a consensus: trusted and mutual agreement that the thing is true.

If we want to criticise particular claims of consensus, that is one thing. But we should never say that we have access to fact, when all we have access to is consensus.

John (F and A), when we’re thinking about “consensus”, I think that it’s helpful to think of some practical circumstances e.g. medical treatments for some specific conditions, think of a noncontroversial one. These issues have debated under the term “evidence-based medicine”. There has been some controversy in recent years over how “review articles” are put together. Many of the issues seem comparable to me. I’d be more inclined to compare the “consensus” on climate to the consensus on certain forms of medical treatment, rather than to the consensus on the view that e=mc2.

Also in terms on reliance on reports from large committees of climate scientists: think about other types of decision making. If you were building a refinery or a steel mill, would you go about selecting a process by having large meetings of experts at frequent intervals at pleasant locations around the world and asking them to recommend a process? Or would you hire Bechtel or someone like that? There’s a level of engineering consideration that sure seems missing to me. Engineers go through details, check calculations, it’s done all the time. They do specific tests and feasibility studies.

Or let’s suppose that for some reason world leaders had taken it into their heads 10 years ago to create an International Panel on Curing Cancer with seemingly unlimited budgets for meetings. Then suppose they asked this IPCC to produce recommendations. I’m sure that they would deliver all sorts of lurid projections about increasing cancer rates in the year 2100 and recommend vast amounts of new research. It would probably work a lot like the present IPCC. This doesn’t mean that any conclusions of the IPCC are wrong, but just that the isntitutional biases of this type of program shouldn’t surprise anyone.
Steve

As I read through this, I kept thinking of Thomas Kuhn, so I’m glad his name was brought up. And unlike Mr. Fleck, I don’t think Crichton’s words stray that far from what Kuhn was saying — or from what science history tells us. When Crichton talks about “consensus,” I think he means “justifying an opinion or an action based on the percentage of scientists who believe it.” Again and again in history we see cases where the majority is wrong; Kuhn himself cites many examples. The best science is that which explains the most about the phenomenon in question (“To be accepted as a paradigm, a theory must seem better than its competitors, but it need not, and in fact never does, explain all the facts with which it can be confronted”). But sometimes facts change, or new ones emerge which may run counter to the paradigm.

According to Kuhn, normal science “is predicated on the assumption that the scientific community knows what the world is like”…”normal science often suppresses fundamental novelties because they are necessarily subversive of its basic commitments.” Paradigm-based research is “an attempt to force nature into the preformed and relatively inflexible box that the paradigm supplies.” Kuhn adds that most scientists are engaged in mop-up operations, much of which is intended to stifle dissent for the prevailing paradigm.

I often hear people say things like “the vast majority of credible scientists believe global warming….” and I think “so what?” Does AGW theory “explain all the facts with which it can be confronted”? If so, does it matter how many scientists believe it? If not, does it matter how many scientists believe it?

The vast majority of climate scientists believed Gilbert Walker was wrong about ENSO. The vast majority of geologists believed J. Harlan Bretz was wrong about the Missoula floods. The vast majority of geologists believed Alfred Wegener (a meteorologist, for goodness sake!) was wrong about continental drift. I could go on and on…

I only wish we could excise the phrase “the vast majority believe…” from our collective vocabulary because it doesn’t mean squat! I suspect Dr. Crichton would agree.

John Fleck: You are right. What Crichton is suggesting not explicitly what Kuhn has described as the progress of normal science. His language is confusing. When he says science is the opposite of consensus he means it should avoid blind conformity in favor of the possibility of revised consensus based on new evidence. I was merely suggesting that Crichton’s slab handed assessments of the nature of science are on the right track: if the paradigm fails to answer the question, and a better solution exists, then test your mettle and publish something. The examples of paradigm shifting science he gives in the speech were along such lines.

Ultimately I suspect Crichton is confused and thinks of himself as a scientist and historian of science instead of his truer nature – a marketeer of science.

I would ask you, John: when you face a medical decision, do you attempt to see what the bulk of experts in the field say should be done and then follow that course of action? Or do you follow the Crichton/Iraq example, and assume they must be wrong and do the opposite? I happen to believe asking the smartest people we can find for their consensus view remains a good choice, which is why we do it all the time. I think you’re right that a consensus isn’t worth much “in the absence of cold, hard, evidence that has been checked and audited and replicated,” and that’s what’s happening now.

I think there’s a false dichotomy in your argument. I am not a contrarian (despite John Hunter flinging that absurdity in my direction). It does not make sense to me to disregard what experts are telling us, providing that the evidence presented has be tested and replicated. A scientific consensus without verification is a confluence of opinion – it does not equal a single empirical data point.

But history has thrown up many examples of scientific consensuses that were wrong, and despite being wrong, continues to disregard and suppress the truth using political power. Scientists, especially modern climate scientists, are very blind to their own prejudices and biases on occasion, and are loathe to accept their own error. For this reason alone, Kuhn remarked that science advances “one funeral at a time”.

Scientific consensuses are at best stop-gaps for knowledge we do not yet have, but they are not knowledge, and left to themselves, rapidly turn into political quagmires. I used the example of the Iraq War as a classic example that expert consensuses do not mean that anything is there, and in my view Bush threw caution to the wind, when caution and waiting for solid fact would have been better.

So it is with the Kyoto Protocol and the nature of this “scientific consensus”. It is a confluence of opinion in the absence of unambiguous evidence. If the Kyoto Protocol is actually about reducing climate change, why is it so ineffective? If climate models are so accurate, why can’t they predict something, instead of being used to rewrite the past? Why does climate science feel it can behave in a partisan and political fashion and yet scream in horror when real partisans and politicians get involved? Why do some climate scientists feel it necessary to constantly misconstrue or malign other researchers based upon their supposed links to fossil fuel companies rather than deal with evidence in a professional manner?

When I talk to scientists about Einstein’s Theory of Relativity, I get chapter and verse on its mathematical robustness and its 100% empirical record. No consensuses are invoked, and I am encouraged to ask tough questions about its implications without anyone impugning my possible links to shadowy Newtonian thinktanks.

Getting back to your point, when faced with a medical crisis, I rely on experts. But if large amounts of money are involved, then no-one is immune from error and checking and auditing of types of treatments, types of drugs, dosages, surgical success is a requirement of all modern healthcare programs. I rely on a consensus of experts to tell me what the consensus is, but also to rigorously check that that consensus continues to be backed up by unimpeachable empirical data.

Getting back to MBH98, I see an untested and unvalidated study which flies in the face of most studies carried out before and quite a few since, being written into a bureaucratic and unneccessary review of the state of climate science and being unjustifiably promoted as the “consensus view” – then when someone checks the method and finds very large flaws, the screaming begins.

The word consensus has two common meanings. One is a general agreement among the members of a given group or community. The other is as a theory and practice of getting such agreements e.g. Consensus decision-making. The first arises naturally ( if it is to exist at all) because many independant lines of thought or study converge to a common point. The second is negotiated ( like Kyoto )and is likely to be a compromise between competing points of view. I see Chrichton’s view as a criticsm of the latter as a way of conducting science and I agree. If John Fleck takes consensus to mean the former then I agree with him.

“Ah consensus … the process of abandoning all beliefs, principles, values and policies in search of something in which no one believes, but to which no one objects; the process of avoiding the very issues that have to be solved, merely because you cannot get agreement on the way ahead. What great cause would have been fought and won under the banner ‘I stand for consensus’?”

Meteorologist Likens Fear of Global Warming to ‘Religious Belief’
With respect to science, the assumption behind the [alarmist] consensus is science is the source of authority and that authority increases with the number of scientists [who agree.] But science is not primarily a source of authority. It is a particularly effective approach of inquiry and analysis. Skepticism is essential to science — consensus is foreign,” Lindzen said.http://www.marshall.org/article.php?id=265
Climate Alarm- Where Does It Come From?http://www.marshall.org/article.php?id=264

A while back, when I mentioned to someone (a physician) that there was no consensus concerning climate change due to human causation, he curtly informed me that in science consensus was arrived at by way of the number of literature reviews stating as much within climatology (or any science, for that matter). Now I know that consensus can mean many things, but can one actually say that a consensus across an entire scientific field of inquiry is stated or established by way of literature reviews or review articles?

Has anybody actually surveyed every (peer-reviewed) paper with respect to climate change to assume to know that there has been an affirmative consensus by way of the literature? Is this a reasonable way in which to assume a consensus? My impression is that many climatologists and climate researchers rarely provide an assertion either way in their papers.

Consensus an a narrow sub-discipline of one area of research (maize genetics, say) and consensus on the broadest cross-cutting quesiton ever encountered in the history of science (AGW) are two different things entirely.

Teaching junk science by consensus makes sense among geostatistocrats who deny that each distance-weighted average has its own variance. The problem is that a pair of measured values, determined in samples selected at positions with different coordinates, defines an infinite set of distance-weighted averages AKA kriged estimates, a zero pseudo kriging variance, and zip degrees of freedom. This is why too few geoscientists know how to test for spatial dependence between measured values in ordered sets, and how to derive sampling variograms that show where orderliness in our sample space of time dissipates into randomness.

Consensus an a narrow sub-discipline of one area of research (maize genetics, say) and consensus on the broadest cross-cutting quesiton ever encountered in the history of science (AGW) are two different things entirely

Astute observation. Yes, AGW is a fundamental paradigm change in science and has consequences for the whole of society. It’s as significant as Copernican or Darwinian theory and must not be accepted as true based on the esoteric “knowledge” of a handful of scientists.